Time to dust off the Python skills...

So, using Python, I am working on a project where you enter the month and it will tell you that month's birthstone. I got that far, but there's a few things I need to fine tune, and I need your help.

1. When I enter the month, it needs to be in a format of August, or July. I need to make it so I can enter the month in any case lettering, such as august, AUGUST, or AuGuSt. I'm not sure how to do this.

2. If the user enters anything else other than the month, I need a message that says "Invalid entry. Please enter a month: " or something along those lines.

Your help is greatly appreciated (that is if I get any). Here's the code I have so far:

I tried the string idea (which was a good idea), but strings and lists are two different things. A command for a string won't work with the list. And no, I can't just enter all of the forms of the months because for one it would be annoying, and two, there is an easier way somehow, and that's what I'm trying to figure out. But thanks for all of the help so far, didn't think I was going to get any.